Process of making dental dies.



No. 745,615. PATENTED/DEG. 1, 1903;

. 0. A. HOLMES.

- I PROCESS OF MAKING DENTAL DIES.-

APPLICATION FILED MAR. 31, 1903.

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WITNESSES 1N VEN TOR.

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No. 745,615. I

UNITED STATES Patented December 1, 1903.

PATENT OFFICE.

CLARENCE ADELBERT HOLMES, OF SEATTLE, WASHINGTON.

PROCESS OF MAKING DENTAL DIES.-

SPECIFICATION forming part of Letters Patent No. 745,615, dated December 1, 1903.

Application filed March 31, 1903. Serial No. 150,480. (No specimena) To aaZZ whom it may concern:

Be it known that I, CLARENCE ADELBERT HOLMES, a citizen of the United States of America, and a resident of the city of Seattle, in the county of King and State of Washington, have invented certain new and usefulImprovements in Processes of Making Dental Dies, of which the following is a specification.

My invention relates to improvements in the art of making dies used in the production of artificial dentures.

Among numerous objects attained by this invention and readily understood from the following specification and accompanying drawings, included as a part thereof, is a simplified process by which dies employed in making denture-plates are expeditiously and more perfectly formed at comparatively small cost.

lhe above-mentioned and other desirable objects are attained. by the process set forth in the following specification and particularly pointed out in the appended claims.

With reference to the drawings filed herewith and bearing like reference characters for corresponding parts throughout, Figure l is a view in perspectiveshowing the preferred form of the die-head. Fig. 2 is a like view showing the die-head and impression or mold combined as a flask. Fig. 3 is a transverse section of the die-head and impression or mold, taken on line 3 3 of Fig. 2 and shows the die cast and in like section; and Fig. 4 is a view in perspective showingthe die as ap-.

plied to form a denture-plate.

To form a die,as 10,by my improved process for use in making a denture base or the like, an impression is first taken in suitable plastic material of the part it is desired to fit with a plate, and molten metal is then poured into this impression or mold while the material in which the same has been taken is damp or green. As now considered, this die 10 is formed from fusible metal which will melt at substantially 212 Fahrenheit, so that it can be conveniently melted by immersing it in boiling water, and it is preferably made of a the cast is made and has consequently not been contorted or reduced in size by shrinkage thedie will come from the mold with the active surface or face true in form and size relatively to the model or part from which the impression was taken.

In the present consideration the impression is taken in suitable plastic material, such as plaster-of-paris, which is placed in a suitable tray, as 12 or thelike, having a handle 14:, by means of which the tray is placed in the mouth and the impression made by pressing the plaster bed, as 11, while in a plastic condition against the part it is desired to fit with aplate; The tray is then removed from the mouth with this mold or impression and preferably placed with the impressed surface of the mold opposing the face of a suitable body, as 15, of comparatively refractory material, as iron or the like, to form a flask. As now considered this refractory body is renderedof suitable form to serve as a head for manipulating the die and is provided with a suitable dovetailed channel or groove, as 16, in the face, so that the die will be conveniently conjoined with the head in casting, and this channel or groove is preferably formed substantially U shape, with the ends of the stems extending to the side edge of the head, so that the molten metal can be conveniently poured into one stem, while the air and resultant gases of the pour will find escape at the outer end, and the head is formed with the face of suitable size and shape to leave a projecting marginal surface about the tray when in place thereon, so that the mold and the die-head can be conveniently secured together as a flask for casting by means of a joint of plaster-of-paris, as 17.

By using the comparatively refractory diehead the quantity of alloy necessary for the die is reduced to a minimum and a substantial impact surface provided to receive the blows of a hammer or mallet as required in forming the plate, while the alloy from which the die is formed will be more quickly congealed by coming in contact with this head, and the same portion of alloy can be used repeatedly to form successive dies, and, owing to the minimum amount of alloy required when the die-head is employed, the loss in repeated meltings thereof is very small.

In proceeding by my process to form a die suitable for making a base-plate for a full denture, for example, the usual preparatory step of taking an impression from the mouth in a bed of plaster-of-paris supported in a tray of the ordinary form is first proceeded with. The impression or mold thus made is then immediately placed in position on the face of the die-head to form the flask, which is then set in an upright position with the open end of the channel uppermost, Fig. 2, and the melted alloy then poured, and after the alloy has congealed the impression or mold is removed from the die-head. The die is now ready for use to form the plate and is preferably employed for this purpose in combination with a suitable cup-shaped base, as 18, in which a yielding bed composed of loose shot, soap, or the like is provided and upon which the blank plate is placed. The die is then set upon this blank and a hammer or mallet employed to strike the die-head, and thereby conveniently force the die to bend the blank in the ordinary and well-known manner.

A die formed by this process will make a perfectly-fitting denture, owing to the fact that there will be no perceptible shrinkage of either the plastic impression or of the alloy from which the die is formed. Furthermore, the die can be used almost immediately following the taking of the impression and the plate tried in place before the patient leaves the office.

Having thus described my,invention, what I claim as new, and desire to secure by Letters Patent of the United States of America, is-

1. In the formation of dental dies; the process which includes taking an impression in suitable material from the mouth, and immediately pouring molten metal into mold thus formed.

2. In the formation of dental dies; the process which includes the making of an impression in suitable plastic material, and pouring molten metal into the impression when the said plastic material is green.

3. In the formation of dental dies; the process which includes taking an impression in suitable material, placing the mold thus formed with the impressed surface opposing a body of comparatively refractory material and pouring molten metal of comparatively low fusing quality into the flask thus formed.

4. In the formation of dental dies; the process-which includes taking an impression in suitable plastic material from the mouth, placing the mold thus formed with the impressed surface opposing a body of comparatively refractory material, and pouring molten metal of comparatively low fusing quality into the flask thus formed While said mold is green.

5. In the formation of dental dies; the process which includes taking an impression in suitable material from the mouth, and pouring molten metal of a low fusing quality into the mold thus formed before the impressed surface of said material is dry.

6. In the formation of dentaldies; the process which includes taking an impression in plastic material from the mouth, placing the mold thus formed with the impressed surface opposing the face of a die-head composed of comparatively refractory material, and pouring molten metal of low fusing quality into the flask thus formed while the said plastic material is green.

7. In the formation of dental dies; the process which includes taking an impression in plastic material from the mouth, placing the mold thus formed with the impressed surface opposing the face of a die-head carrying means for conjoining the die therewith as cast, and pouring-molten metal of low fusing quality into the flask thus formed while the said plastic material is green.

8. In the formation of dentaldies; the process which includes taking an impression in plastic material from the mouth, placing the mold thus formed with the impressed surface opposing the face of a die-head composed of comparatively refractory material and having a substantial U-shaped channel in said face with the stems extending to the edge of the face, and pouring molten metal into the flask thus formed before the said plastic material is dry.

9. In the formation of dental dies; the process which includes making an impression in plastic material, placing the mold thus formed with the impressed surface opposing the face of a die-head composed of comparatively refractory material and having a substantially U shaped channel in said face with the stems extending to the edge of the face, and pouring molten metal into said channel from one end while the said plastic material is green.

10'. In the formation of dental dies; the process which includes taking an impression in suitable plastic material from the mouth, placing the mold thus formed with the impressed surface opposing the face of a diehead composed of comparatively refractory substantially of bismuth sixteen parts, tin five parts and lead ten parts into the flask thus formed while the said plastic material is green.

Signed at Seattle, Washington, this 21st 15 day of March, 1903.

CLARENCE ADELBERT HOLMES. Witnesses: .i

W. PARRY SMITH, 1 L. H. PONTIUS. 

